Effect of different concentrations of carbamide peroxide on the staining susceptibility of resin composites

Abstract

Context:Bleaching can affect the surface properties of resin composites.Aims:The aim of this study was to evaluate the effect of three regimens of carbamide peroxide (CP) on staining susceptibility of silorane and methacrylate-based resin composites.Methods:In this study, 80 composite disks were prepared from A2 shade of P90 and Z250 composite resins (40 each). Samples were divided into three test groups based on the CP concentration (10%, 16%, and 22%) and bleached for 14 days. Controls were kept in distilled water. Then, specimens were immersed in a tea solution for 14 consecutive days. A spectrophotometer was used to measure the specimen colors in CIE L*a*b system, initially and after staining. Data were analyzed using SPSS 16 software using two-way ANOVA, t-test, and Tukey honestly significant difference tests at α = 0.05.Results:The color susceptibility of Z250 samples were significantly affected in groups bleached with 22% CP compared to the controls (P = 0.001). The different concentrations of CP did not affect the staining susceptibility of the P90 samples (P > 0.05).Conclusions:Bleaching of the tested resin composites did not increase their susceptibility to extrinsic staining in vitro except for the Z250 samples bleached with 22% CP.

Effect of Laser and Conventional Office Bleaching and Polishing on the Color Change of Stained Nanohybrid and Microhybrid Composite Resin

“…Therefore, composite resins with a higher resin content become susceptible to degradation and, as a result, to color changes. For example, composite resins with a higher filler content undergo more color changes in the long term [29,30].…”

Effect of Polishing on the Surface Microhardness of Nanohybrid Composite Resins Subjected to 35% Hydrogen Peroxide

“…Furthermore, peroxides have been reported to induce the separation of the polymer chain that constitutes a composite resin, causing its double bonds to become vulnerable, resulting in a softening of the surface and deep layers of the restorative material, thus affecting the durability and clinical success of dental restorations. [ 16 17 ] In addition, Esmaeili et al . [ 17 ] stated that the mechanism of action of bleaching agents on tooth structures is based on the oxidation of dentin molecules, causing a change in color.…”

“…[ 16 17 ] In addition, Esmaeili et al . [ 17 ] stated that the mechanism of action of bleaching agents on tooth structures is based on the oxidation of dentin molecules, causing a change in color. From these statements, we can interpret that the oxidation reaction caused by the hydrogen peroxide-based bleaching agent interferes with the structural integration of composite resins, mainly influencing their organic matrix, facilitating water absorption and particle loss, as well as causing an alteration of the interface between the filler and the matrix, which would affect the topography of the resin surface and thus cause a decrease in the surface microhardness.…”